package com.itheima.reggie.controlller;


import com.itheima.reggie.common.R;
import com.itheima.reggie.mapper.DishMapper;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;


import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;


/**
 * 文件上床与下载
 *
 */

@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {

    private final DishMapper dishMapper;
    @Value("${reggie.path}")
    private String basePath;

    public CommonController(DishMapper dishMapper) {
        this.dishMapper = dishMapper;
    }


    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //file是一个临时文件 需要转存到指定位置，否则本次请求完成后临时文件会被删除
        log.info("文件信息{}",file.toString());
        //获取原始文件名
        String originalFilename = file.getOriginalFilename();
        String suffix = originalFilename.substring(originalFilename.lastIndexOf(".")); //动态获取文件后缀 .jpg
        
        //使用UUID重新生成文件名，防止文件名称重复 造成文件重复  
        String fileName = UUID.randomUUID().toString()+suffix;

        //需要创建一个目录对象
        File dir=new File(basePath);
        if(!dir.exists()){
            dir.mkdirs();}
        try {
            file.transferTo(new File(basePath+fileName));
        }catch (IOException e){
            e.printStackTrace();
        }
        return R.success(fileName);
    }

    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){

        try {
            //输入流 读取文件内容
            FileInputStream fis = new FileInputStream(new File(basePath+name));
            //输出流 通过输出流将文件写回到浏览器，在浏览器展示图片
            ServletOutputStream out = response.getOutputStream();
            //设置相应的内容的类型
            response.setContentType("image/jpeg");

            int len=0;
            byte[] buffer = new byte[1024];
            while((len=fis.read(buffer))!=-1){
                out.write(buffer,0,len);
                out.flush();
            }
            out.close();
            fis.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
